Indoxyl derivatives and process of making same.



Nin SATES ATENT (Enema AUGUST STOCK, OF HOCHST-ON-THE-MAIN, GERMANY,ASSIGNOR TO THE FARBWERKE, VORMALS MEIS'IER, LUOIUS & BRUNING, OF SAMEPLACE.

INDOXYL DERIVATIVES AND PROCESS OF MAKlNG SAME.

SJPEGIFIGATION forming part of Letters Patent No. 662,703, datedNovember 27, 1900;

' Application filed July 5, 1898. serial No. 685,156- (No specimens.)

To all whom it may concern.-

Be it known that LAUeUsT STooK, Ph. D., a citizen of the Empire ofGermany, residing at Hochst-on-the-Main, Germany, have invented certainnew and useful Improvements in the Manufacture of Derivatives ofIndoxyl, of which the following is a specification.

This invention relates to the manufacture importance in the productionof indigo and its hoinologues.

It is known that acid ethers when treated with sodium alcoholate ormetallic sodium react in splitting off alcohol with such acid ethers andketones as contain in the neighborhood of the carbonyl group a methyl ora methylen group. By this reaction the sodium coinpounds of ketonic acidethers and dike-tones of derivatives of indoxyl, which are of great areformed after the following equations:

0 O ONa O i (J H --C CH -C N :GH (J H-O ROH H s 5 OR+ a OR+ a t 5 OR+Beneztciligracid Acetic ELCRL SOdiunL Sodium coggpiinlflpglthe benzoylAilio: Hgyedlro- O O ONa O o,H -o +OH O CH +Na:O H -O HO OH +ROH+H oR oBenaztpxigracid Acetone Sodium Sodium comgguigeof the benzoyl iltllgp-Hgpgrllro- O O ONa O C H 0 CH O O Hfi-Na C 11 O H O O H +ROH+H on ogfiig f Acetophenon. Sodium.

' Acids separate from these sodium compounds the ketone acid ethers andthe diketones them selves, for which, besides the above formulas, thefollowing are to be taken into considera- Sodium compound of the benzoylAlco- Hydroacetophenon. gen.

O O H benzoylacetophenon.

tion: An analogous reaction takes place intermo- Y O lecularly by theaction of sodium alcoholate 4 I or metallic sodium upon the others ofaro 06115 0 CH2 benzoylacetlc ethel" matic ortho-amido-carbonio acids,which contain at the nitrogen atom the group O O O O H -O OH -O OHbenzoylacetone. -OH -O For instance:

0 1-1 o ONa C o o o /GH C +Na: OOOO H +G H -OH+H 00 H 2 5 H HDiethylether ogopltiigigiglycin ortho-car- SodiumEthyletglplflilngggggggpnic acid, Afllgp- Hggigo- For producingindoxylmethylketone the process may be carried out as follows: twentyparts, by weight, of ethyl ether of acetonylanthranil acid obtained bycombining ethyl 5 ether of anthranil acid with chloracetone aredissolved in ten times their quantity of benzene (or any otherindifierent dissolving agent) and 2.3 parts of sodium finely divided areadded. To start the reaction, it is ad IO visable to add a few drops ofalcohol and to aid it by heating slowly. Thus the sodium compound of theindoxylmethylketone soon separates with a rapid generation of hydrogenas a white precipitate. When all the sodium 1,- has disappeared, it isallowed to cool and then agitated with a dilute acid, whereby theindoxylmethylketone is separated from the sodium compound. By removingthe benzene layer and distilling off the benzene the indoxylmethylketoneis obtained as an oil, which soon coagulates in a crystalline form.

The indoxylmethylketone is a weak yellow body easily turning a littledarker in the air. The compound melts at 153. It is easilysoluble inether, alcohol, and hot benzene and difiicultly soluble in chloroform.The indoxylmethylketone is soluble in caustic alkalies and isreseparated from this solution by means of acids.

When heated with caustic alkali,an intense yellow melt is formed, whichdissolved in water separates indigo when exposed to the air.

Concentrated sulfuric acid dissolves the ke tone with a yellow color,which turns on heating and in consequence of the formation of indigofrom green to. blue.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. The herein-described process of manufacturingindoxyl derivatives, consisting in treating with sodium thosederivatives of the ethers of aromatic ortho-amido-carbonic acid whichcontain at the nitrogen atom the group AUGUST STOCK.

Witnesses HEINRICH HAHN, BERNHARD LEYDEOKER.

